Move call to get the lease time and the setup of the state
renewal out of nfs4_create_session so that it can be called
after clearing the DRAINING flag.  We use the getattr RPC
to obtain the lease time, which requires a sequence slot.
Signed-off-by: NRicardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We no longer need to maintain a distinction between nfs41_sequence_done and
nfs41_sequence_free_slot.

This fixes a number of slot table leakages in the NFSv4.1 code.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We should not assume that nfs41_init_clientid() will always want to
initialise the session. If it is being called due to a server reboot, then
we just want to reset the session after re-establishing the clientid.

Fix this by getting rid of the 'reset' parameter in
nfs4_proc_create_session(), and instead relying on whether or not the
session slot table pointer is non-NULL.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This patch invokes RECLAIM_COMPLETE after the client is done
reclaiming state.

There are interpretations of the spec that suggest that
RECLAIM_COMPLETE should also be issued after a new clientid
has been obtained from the server and even if there is no
state to reclaim.  This tells the server that the client
has no state to reclaim even if the client isn't aware the
server may have rebooted.
Signed-off-by: NRicardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Implements RECLAIM_COMPLETE as an asynchronous RPC.
NFS4ERR_DELAY is retried, NFS4ERR_DEADSESSION invokes the error handling
but does not result in a retry, since we don't want to have a lingering
RECLAIM_COMPLETE call sent in the middle of a possible new state recovery
cycle.  If a session reset occurs, a new wave of reclaim operations will
follow, containing their own RECLAIM_COMPLETE call.  We don't want a
retry to get on the way of recovery by incorrectly indicating to the
server that we're done reclaiming state.

A subsequent patch invokes the functionality.
Signed-off-by: NRicardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

XDR encoding and decoding for RECLAIM_COMPLETE.  Implements the necessary
encoding to indicate reclaim complete for the entire client.  In the future,
it can be extended to provide reclaim complete functionality for a single
file system after migration.
Signed-off-by: NRicardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NRicardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Otherwise we have no guarantees that other processes won't start another
RPC call while we're resetting the session.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

in NFSv4.1 the seqid part of a stateid in CB_RECALL must be 0
Signed-off-by: NAlexandros Batsakis <batsakis@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

the server can indicate a number of error conditions by setting the
appropriate bits in the SEQUENCE operation. The client re-establishes
state with the server when it receives one of those, with the action
depending on the specific case.
Signed-off-by: NAlexandros Batsakis <batsakis@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The v4.1 client should take into account the desired rsize, wsize when
negotiating the max size in CREATE_SESSION. Accordingly, it should use
rsize, wsize that are smaller than the session negotiated values.
Signed-off-by: NAlexandros Batsakis <batsakis@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NAlexandros Batsakis <batsakis@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

In v4.1 the client MUST/SHOULD use the EXCLUSIVE4_1 flag instead of
EXCLUSIVE4, and GUARDED when the server supports persistent sessions.
For now (and until we support suppattr_exclcreat), we don't send any
attributes with EXCLUSIVE4_1 relying in the subsequent SETATTR as in v4.0
Signed-off-by: NAlexandros Batsakis <batsakis@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NAlexandros Batsakis <batsakis@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

For now the clients returns _all_ the delegations of the specificed type
it holds
Signed-off-by: NAlexandros Batsakis <batsakis@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NAlexandros Batsakis <batsakis@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NAlexandros Batsakis <batsakis@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The NFSv4.1 spec-29 (18.36.3) says that the server MUST use an ONC RPC
(program) version number equal to 4 in callbacks sent to the client.
For now we allow both versions 1 and 4.
Signed-off-by: NAlexandros Batsakis <batsakis@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Replace sync and async handlers setting of the NFS4CLNT_SESSION_SETUP bit with
setting NFS4CLNT_CHECK_LEASE, and let the state manager decide to reset the session.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Do not wake up the next slot_tbl_waitq task in nfs4_free_slot because we
may be draining the slot. Either signal the state manager that the session
is drained (the state manager wakes up tasks) OR wake up the next task.

In nfs41_sequence_done, the slot dereference is only needed in the sequence
operation success case.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If the session is reset during state recovery, the state manager thread can
sleep on the slot_tbl_waitq causing a deadlock.

Add a completion framework to the session.  Have the state manager thread set
a new session state (NFS4CLNT_SESSION_DRAINING) and wait for the session slot
table to drain.

Signal the state manager thread in nfs41_sequence_free_slot when the
NFS4CLNT_SESSION_DRAINING bit is set and the session is drained.
Reported-by: NTrond Myklebust <trond@netapp.com>
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

nfs4_recover_session can put rpciod to sleep. Just use nfs4_schedule_recovery.
Reported-by: NTrond Myklebust <trond.myklebust@netapp.com>
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Do not fall through and set NFS4CLNT_SESSION_RESET bit on NFS4ERR_EXPIRED
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Do not fall through and call nfs4_delay on session error handling.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

nfs4_read_done returns zero on unhandled errors. nfs_readpage_result will
return on a negative tk_status without freeing the slot.
Call nfs4_sequence_free_slot on unhandled errors in nfs4_read_done.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

nfs41_sequence_free_slot can be called multiple times on SEQUENCE operation
errors.
No reason to inline nfs4_restart_rpc
Reported-by: NTrond Myklebust <trond.myklebust@netapp.com>

nfs_writeback_done and nfs_readpage_retry call nfs4_restart_rpc outside the
error handler, and the slot is not freed prior to restarting in the rpc_prepare
state during session reset.

Fix this by moving the call to nfs41_sequence_free_slot from the error
path of nfs41_sequence_done into nfs4_restart_rpc, and by removing the test
for NFS4CLNT_SESSION_SETUP.
Always free slot and goto the rpc prepare state on async errors.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Make this clear by calling rpc_restart-call.
Prepare for nfs4_restart_rpc() to free slots.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The bit is no longer used for session setup, only for session reset.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Reported-by: NTrond Myklebust <trond.myklebust@netapp.com>

Resetting the clientid from the state manager could result in not confirming
the clientid due to create session not being called.

Move the create session call from the NFS4CLNT_SESSION_SETUP state manager
initialize session case into the NFS4CLNT_LEASE_EXPIRED case establish_clid
call.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

NFS4ERR_FILE_OPEN is return by the server when an operation cannot be
performed because the file is currently open and local (to the server)
semantics prohibit the operation while the file is open.
A typical case is a RENAME operation on an MS-Windows platform, which
prevents rename while the file is open.

While it is possible that such a condition is transitory, it is also
very possible that the file will be held open for an extended period
of time thus preventing the operation.

The current behaviour of Linux/NFS is to retry the operation
indefinitely.  This is not appropriate - we do not expect a rename to
take an arbitrary amount of time to complete.

Rather, and error should be returned.  The most obvious error code
would be EBUSY, which is a legal at least for 'rename' and 'unlink',
and accurately captures the reason for the error.

This patch allows a few retries until about 2 seconds have elapsed,
then returns EBUSY.
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The d_instantiate(new_dentry, NULL) is superfluous, the dentry is
already negative.  Rehashing this dummy dentry isn't needed either,
d_move() works fine on an unhashed target.

The re-checking for busy after a failed nfs_sillyrename() is bogus
too: new_dentry->d_count < 2 would be a bug here.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Move unhashing the target to after the check for existence and being a
non-directory.

If renaming a directory then the VFS already unhashes the target if it
is not busy.  If it's busy then acquiring more references during the
rename makes no difference.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Comments are wrong or out of date.  In particular d_drop() doesn't
free the inode it just unhashes the dentry.  And if target is a
directory then it is not checked for being busy.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

VFS already checks if both source and target are directories.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

When the "rsize=" or "wsize=" mount options are not specified,
text-based mounts have slightly different behavior than legacy binary
mounts.  Text-based mounts use the smaller of the server's maximum
and the client's maximum, but binary mounts use the smaller of the
server's _preferred_ size and the client's maximum.

This difference is actually pretty subtle.  Most servers advertise
the same value as their maximum and their preferred transfer size, so
the end result is the same in most cases.

The reason for this difference is that for text-based mounts, if
r/wsize are not specified, they are set to the largest value supported
by the client.  For legacy mounts, the values are set to zero if these
options are not specified.

nfs_server_set_fsinfo() can negotiate the transfer size defaults
correctly in any case.  There's no need to specify any particular
value as default in the text-based option parsing logic.

Note that nfs4 doesn't use nfs_server_set_fsinfo(), but the mount.nfs4
command does set rsize and wsize to 0 if the user didn't specify these
options.  So, make the same change for text-based NFSv4 mounts.

Thanks to James Pearson <james-p@moving-picture.com> for reporting and
diagnosing the problem.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Recent changes to snprintf() introduced the %pI6c formatter, which can
display an IPv6 address with standard shorthanding.  Use this new
formatter when displaying IPv6 server addresses in /proc/mounts.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>